Field of the Invention
The invention relates to a substrate, and more particularly, to a carrier substrate suitable for carrying components.
Description of Related Art
In recent years, with the rapid progress of the electronic technology, high-tech electronic industries have appeared one after another, thus more human-oriented, more performance-preferred electronic products are continuously evolving new things from the old, and have been designed to cater to the trend of being low-profiled and compact-sized. A carrier substrate is usually disposed in the electronic products. The carrier substrate, in addition to having conductive circuits, can also carry components such as capacitors, inductors, resistors, IC chips, or package bodies to be used as data processing units of electronic products.
However, the connection pads and the traces on the known carrier substrate are on the same horizontal plane, and the openings of the solder mask layer expose the connection pads and the traces in the pre-connection region at the same time. Therefore, the arrangements not only affect electrical performance by readily generating oxidation phenomenon to the traces, the user also cannot easily distinguish the connection pads from the traces, and therefore the component cannot be directly connected with the connection pads accurately. Therefore, effectively allowing the user to directly connect the component to the connection pads and preventing the traces from being exposed from the outside of the solder mask layer are one of the goals industries today are actively working toward.